Embolic Protection Catheter and Related Devices and Methods

ABSTRACT

Embolic material capture catheters and related devices and methods constrain a distal end portion of an embolic material capture element in an insertion configuration. A method of deploying an embolic material capture element in a blood vessel includes constraining a distal end portion of the embolic material capture element in an insertion configuration via engagement with a dilator assembly. The embolic material capture element, in the insertion configuration, is advanced through the blood vessel. A deployment cap of the dilator assembly is distally advanced relative to a dilator sheath of the dilator assembly to release the distal end portion of the embolic material capture element from engagement with the dilator assembly to reconfigure the embolic material capture element from the insertion configuration to a fully deployed configuration via self-expansion of the embolic material capture element.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is a Continuation of U.S. patent applicationSer. No. 16/703,633 filed Dec. 4, 2019 (Allowed); which is aContinuation of U.S. patent application Ser. No. 16/422,532 filed May24, 2019 (now U.S. Pat. No. 10,561,488); which is a Continuation-in-Partof PCT/US2018/067143 filed Dec. 21, 2018; which claims the benefit ofU.S. Provisional Appln No. 62/611,454 filed Dec. 28, 2017; thedisclosures which are incorporated herein by reference in their entiretyfor all purposes.

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is a proven strategy forthe treatment of severe aortic stenosis that has been validated for usein patients who are not eligible for surgical aortic valve replacement(SAVR) due to patient frailty or associated high operative risk. TAVRwith the use of a self-expanding or balloon-expanded bioprosthetic valvehas been FDA-approved for commercial use in the US in selected patients.TAVR is rapidly becoming the method of choice to treat aortic stenosisin patients deemed to be at increased risk of death if offered atraditional surgical aortic valve replacement. Patients presentlyselected for TAVR, however, are most often elderly with frailty and anumber of comorbidities. The femoral artery is generally the firstchoice for access to the aortic valve. In patients with significantarterial occlusive disease, however, marked tortuosity of the ileofemoral system and/or significant at risk atheromatous plaque within thenative aorta and/or aneurysmal disease may present significant risk forfemoral access such that alternate access TAVR is preferable. Analternative route has been proposed several years ago in the form of atrans-apical (TA) approach through the apex of the left ventricleexposed through a left lateral thoracotomy. The TA approach, however,requires opening the left chest in patients having potential pulmonarydysfunction and the rate of bleeding complications may be higher thanthat observed after traditional trans-femoral (TF) approach. In thesearch for yet another alternative to compromised peripheral arterialvascular access, a direct trans-aortic (TAo) route has been described ina limited number of cases since 2010. In a recent report, the casesperformed through a TAo route represented only 4% of the TAVR casesperformed by 2013.

Although results have been encouraging with TAVR, the risk of stroke hasbeen demonstrated to be significantly higher with TAVR relative to SAVR.Clinically observed stroke (CVA) underestimates the prevalence ofembolic events inherent with TAVR. During TAVR, stent and implantedvalve expansion (with or without the use of a balloon) results in nativevalve compression and radial leaflet displacement that leads to theliberation of tissue and particulate matter that travels distally in thearterial tree. Some of the debris lodges in terminal branches ofcerebral vessels and will be evidenced with new onset stroke. Otherdebris released at the time of TAVR lodge in vessels of the peripheralcirculation, renal circulation, coronary circulation, and mesentericcirculation. These patients may manifest clinical scenario of renalfailure, mesenteric ischemia, peripheral ischemia, and/or myocardialinfarction. Other patients may not have acute clinical deterioration butmay suffer late effects due to impaired functional reserve related tosub-clinical embolic events. The occurrence of embolic events duringTAVR is a significant impediment to offering the technique to largerlower risk groups of patients.

A number of different approaches have been developed for embolicprotection. Existing embolic protection devices are primarily adapted todeflect embolic material from the brachiocephalic vessels or captureembolic material within the brachiocephalic vessels. There are a numberof difficulties with these existing embolic protection devices. First,deployment of the devices requires additional time and can conflict withthe performance of the valve implantation procedure. Second, deploymentof the devices may lead to additional vessel trauma and liberation ofembolic material. Third, the deployment of the devices may be difficultand stability of deployment may make protection less than reliable.Fourth, the devices do not protect the brain from all sources of bloodflow and particularly posterior cerebral blood flow is not filtered.Fifth, systemic embolization may still occur that may lead tointestinal, renal, and/or peripheral manifestations of ischemic gut,renal insufficiency and/or peripheral ischemia. Sixth, coronaryembolization and myocardial infarction may occur due to proximalembolization.

BRIEF SUMMARY

The following presents a simplified summary of some embodiments of theinvention in order to provide a basic understanding of the invention.This summary is not an extensive overview of the invention. It is notintended to identify key/critical elements of the invention or todelineate the scope of the invention. Its sole purpose is to presentsome embodiments of the invention in a simplified form as a prelude tothe more detailed description that is presented later.

In many embodiments, an embolic material capture catheter includes anintegrated embolic material capture element that is deployable within ablood vessel downstream of a treatment site to capture embolic materialreleased from the treatment site from flowing downstream through theblood vessel, thereby preventing associated embolism(s). In manyembodiments, the deployment of the embolic material capture elementincludes an initial deployment phase in which a distal end portion ofthe embolic material capture element is held in a collapsedconfiguration while a proximal end portion is advanced distally towardthe distal end portion, thereby expanding a middle portion of theembolic material capture element. In many embodiments, followingexpansion of the middle portion of the embolic material capture element,the distal end portion of the embolic material capture element isreleased and self-expands into engagement with the blood vessel. In someembodiments, the embolic material capture element is constrained in theinsertion configuration via axial tension applied to the embolicmaterial capture element, thereby enabling the embolic material capturecatheter to have a reduced diameter and/or increased flexibility since aretaining sheath is not required to retain the embolic material captureelement in the insertion configuration. The embolic material capturecatheter can be adapted for use in any suitable procedure. For example,the embolic material capture catheter can be used during implantation ofa prosthetic aortic valve in which the integrated embolic materialcapture element is deployed in a patient's aorta downstream of thepatient's aortic valve to capture embolic material released duringimplantation of the prosthetic aortic valve. In many embodiments, theembolic material capture catheter includes a lumen into which a deliverycatheter for the prosthetic valve can be inserted to advance theprosthetic valve to a implantation site upstream of the deployed embolicmaterial capture element. In many embodiments, the lumen is configuredto accommodate extraction of embolic material captured by the embolicmaterial capture element. In some embodiments, such as embodiments sizedfor insertion through the femoral artery, removal of embolic materialthrough the lumen of the embolic material capture catheter may not bepossible while the delivery catheter for the prosthetic valve isaccommodated in the lumen. In such embodiments, removal of embolicmaterial through the lumen of the embolic material capture catheter canbe accomplished following removal of the delivery catheter for theprosthetic valve from the lumen of the embolic material capturecatheter. The embolic material capture catheter and related treatmentcatheters, devices, and methods are especially suited for use in TAVRvia any suitable access (including, but not limited to, femoral, directaortic access, brachiocephalic, subclavian, axillary or carotidarteries) that enables accurate positioning of the prosthetic aorticvalve.

Thus, in one aspect, an embolic material capture catheter includes anouter sheath, an inner sheath, an embolic material capture element, anda dilator assembly. The outer sheath defines an outer sheath lumen. Theinner sheath is slidably disposed in the outer sheath lumen and definesan inner sheath lumen. The embolic material capture element has aproximal end portion and a distal end portion. The proximal end portionis attached to a distal end portion of the inner sheath. The embolicmaterial capture element has an insertion configuration, an intermediatedeployment configuration, and a fully deployed configuration. Theembolic material capture element is adapted to, in the fully deployedconfiguration, interface with an inner surface of a blood vessel. Insome embodiments, the embolic material capture element is composed of anouter support element and an inner filter element attached to the outersupport element. The outer support element can include one or moremembers that radially expand into contact with the wall of a vesselalong which embolic material is to be blocked from traversing. The innerfilter element can include a filtering device or filtering membraneconfigured to prevent emboli of greater than a particular size frompassing through the filtering device or the filtering membrane. Theouter support element can be configured to provide a framework andstability for the inner filter element to function. The embolic materialcapture element is adapted to block flow of embolic material through theblood vessel past the embolic material capture element. The dilatorassembly includes a dilator sheath and a deployment cap assembly. Thedilator sheath is slidably disposed in the inner sheath lumen anddefines a dilator sheath lumen. The deployment cap assembly is slidablydisposed in the dilator sheath lumen. A distal end portion of theembolic material capture element is restrained in the insertionconfiguration and the intermediate deployment configuration by thedilator assembly. A middle portion of the embolic material captureelement expands radially from the insertion configuration to theintermediate deployment configuration via distal advancement of theinner sheath towards the distal end portion of the embolic materialcapture element restrained by the dilator assembly. The distal endportion of the embolic material capture element expands radially fromthe intermediate deployment configuration to the fully deployedconfiguration in response to release of the distal end portion of theembolic material capture element by the dilator assembly via distaladvancement of the deployment cap assembly relative to the dilatorsheath. The dilator assembly is removable from the inner sheath lumenwhile the embolic material capture element is in the fully deployedconfiguration via proximal retraction of the dilator assembly relativeto the inner sheath.

In many embodiments, the embolic material capture catheter can bereconfigured from the fully deployed configuration to a collapsedcaptured configuration for withdrawal from the patient. For example, inmany embodiments, the embolic material capture element is reconfigurablefrom the fully deployed configuration to a captured configuration inwhich the embolic material capture element is disposed in the outersheath lumen via proximal retraction of the inner sheath relative to theouter sheath.

In many embodiments, the embolic material capture element is retained inthe insertion configuration without a surrounding retention sheath,thereby enabling the embolic material capture catheter to have a reduceddiameter and/or increased flexibility relative to embolic materialcapture catheters that include a surrounding retention sheath. In manyembodiments, the embolic material capture element conforms to an outersurface of the dilator sheath from the proximal end portion of theembolic material capture element to the distal end portion of theembolic material capture element when the embolic material captureelement is in the insertion configuration. In many embodiments, theembolic material capture element has an outer surface that extendsbetween the proximal end portion of the embolic material capture elementand the distal end portion of the embolic material capture element. Inmany embodiments, the outer surface of the embolic material captureelement is disposable distal to the outer sheath with the embolicmaterial capture element in the insertion configuration.

In some embodiments, the embolic material capture element is made atleast partially from a shape-memory material. In some embodiments, theembolic material capture element is retained in the insertionconfiguration at least partially via axial tension imparted into theembolic material capture element via the dilator assembly and the innersheath.

In many embodiments, the embolic material capture catheter is adaptedfor use with a suitable treatment catheter to perform a surgical taskupstream of the embolic material capture element in the fully deployedconfiguration. For example, in many embodiments, the inner sheathaccommodates insertion of a treatment catheter into the inner sheathlumen and advancement of a distal portion of the treatment catheter to aposition distal to the distal end portion of the embolic materialcapture element in the fully deployed configuration. In manyembodiments, the distal end portion of the treatment catheter is adaptedto accomplish a surgical task.

In many embodiments, the embolic material capture catheter is adaptedfor use during implantation of a prosthetic aortic valve. For example,in many embodiments, the embolic material capture element is adapted to,in the fully deployed configuration, interface with a patient's aortaand substantially block flow of embolic material through the patient'saorta past the embolic material capture element. In many embodiments,the treatment catheter is adapted to deploy a prosthetic aortic valve.

In many embodiments, the embolic material capture catheter is adaptedremove embolic material from blood flowing through the blood vessel. Forexample, in many embodiments, the embolic material capture elementincludes a filtering membrane adapted to filter embolic material fromblood flowing through the filtering membrane. In some embodiments, theembolic material capture catheter is adapted to be coupled with anembolic material extraction device operable to draw embolic materialthrough the inner sheath lumen while the embolic material captureelement is in the fully deployed configuration.

In many embodiments, the embolic material capture element includes anouter scaffold portion, an inner filter portion, and an intermediateportion. The outer scaffold portion has an outer scaffold proximal endportion and an outer scaffold distal end portion. The outer scaffoldproximal end portion is attached to the filter sheath distal endportion. The outer scaffold portion is configured to self-expand duringreconfiguration of the embolic material capture catheter from therestrained insertion configuration to the deployed configuration forengagement with a blood vessel inner surface. The inner filter portionhas an inner filter proximal end portion and an inner filter distal endportion. The inner filter proximal end portion is attached to the filtersheath distal end portion. The inner filter portion is configured tocapture embolic material from blood that flows through the inner filterportion. The inner filter distal end portion is coupled with the outerscaffold distal end portion via the intermediate portion. In manyembodiments, the inner filter portion is separated from the outerscaffold portion by an intervening annular space in the deployedconfiguration. In some embodiments, the intermediate portion isconfigured to capture embolic material from blood flowing through theintermediate portion. In some embodiments, the intermediate portion isnonporous. In many embodiments, the intermediate portion has a conicalshape configured to direct blood flow into the inner filter portion.

In some embodiments, the outer scaffold portion, the intermediateportion, and the inner filter portion are portions of an integrallyformed braided wire member. In such embodiments, the embolic materialcapture catheter can include a distal end sheet attached to theintermediate portion that is configured to block flow of embolicmaterial through the intermediate portion. In some embodiments, thedistal end sheet is nonporous. In some embodiments, the distal end sheethas a porosity adapted to filter embolic material out of blood flowingthrough the distal end sheet.

In many embodiments, the outer scaffold distal end portion is configuredfor atraumatic engagement of the blood vessel inner surface. Forexample, in many embodiments, the outer scaffold portion includesdistally extending loops of wires configured for atraumatic engagementof the blood vessel inner surface.

In many embodiments, the embolic material capture element, in the fullydeployed configuration, has a stepped outer diametrical profileconfigured to enhance deployment from the insertion configuration to thefully deployed configuration by substantially isolating contact with theblood vessel to a distal end portion of the embolic material captureelement. For example, in many embodiments, the middle portion of theembolic material capture element has a middle portion external diameterin the fully deployed configuration, the distal end portion of theembolic material capture element has a distal end portion externaldiameter in the fully deployed configuration and the middle portionexternal diameter is less than the distal end portion external diameter.

In another aspect, method of deploying an embolic material captureelement is provided. The method includes constraining a proximal endportion of an embolic material capture element via attachment to adistal end portion of an inner sheath having an inner sheath lumen. Adistal end portion of the embolic material capture element isconstrained in an insertion configuration of the embolic materialcapture element and an intermediate deployment configuration of theembolic material capture element via engagement of the distal endportion with a dilator assembly that extends through the inner sheathlumen. The embolic material capture element, in the insertionconfiguration, is advanced through the blood vessel. The embolicmaterial capture element is reconfigured from the insertionconfiguration to the intermediate deployment configuration by expandinga middle portion of the embolic material capture element disposedbetween the proximal end portion of the embolic material capture elementand the distal end portion of the embolic material capture element viadistal advancement of the inner sheath toward the distal end portion ofthe embolic material capture element constrained by the dilatorassembly. The embolic material capture element is reconfigured from theintermediate deployment configuration to the fully deployedconfiguration via reconfiguration of the dilator assembly to release thedistal end portion of the embolic material capture element fromengagement with the dilator assembly and self-expansion of the distalend portion of the embolic material capture element.

In many embodiments, the method includes capturing the embolic materialcapture element to enable more streamline extraction of the embolicmaterial capture element from the patient. For example, in manyembodiments, the method includes reconfiguring the embolic materialcapture element from the fully deployed configuration to a capturedconfiguration via proximal retraction of the inner sheath relative to anouter sheath to retract the embolic material capture element within anouter sheath lumen of the outer sheath.

In many embodiments of the method, the embolic material capture elementis retained in the insertion configuration without a surroundingretention sheath, thereby enabling the embolic material capture catheterto have a reduced diameter and/or increased flexibility relative toembolic material capture catheters that include a surrounding retentionsheath. In many embodiments of the method, the embolic material captureelement conforms to an outer surface of the dilator assembly from theproximal end portion of the embolic material capture element to thedistal end portion of the embolic material capture element when theembolic material capture element is in the insertion configuration. Inmany embodiments of the method, the embolic material capture element hasan outer surface that extends between the proximal end portion of theembolic material capture element and the distal end portion of theembolic material capture element. In many embodiments of the method, theouter surface of the embolic material capture element is disposabledistal to the outer sheath when the embolic material capture element isadvanced through the blood vessel in the insertion configuration.

In some embodiments of the method, the embolic material capture elementis made at least partially from a shape-memory material. In someembodiments, the method includes retaining the embolic material captureelement in the insertion configuration at least partially via axialtension imparted into the embolic material capture element via thedilator assembly and the inner sheath.

In many embodiments of the method, the embolic material capture catheteris used with a suitable treatment catheter to perform a surgical taskupstream of the embolic material capture element in the fully deployedconfiguration. For example, in many embodiments, method includesadvancing a distal portion of a treatment catheter through the innersheath lumen to a position distal to the distal end portion of theembolic material capture element in the fully deployed configuration. Inmany embodiments, the method includes accomplishing a surgical taskdistal to the distal end of the embolic material capture element in thefully deployed configuration via the treatment catheter. In manyembodiments, the method includes interfacing the embolic materialcapture element in the fully deployed configuration with a patient'saorta, blocking flow of embolic material through the patient's aortapast the embolic material capture element, and deploying a prostheticaortic valve from the distal end portion of the treatment catheter.

In many embodiments, the method includes removing embolic material fromblood flowing through the blood vessel. For example, in manyembodiments, the embolic material capture element includes a filteringmembrane and the method includes filtering embolic material from bloodflowing through the blood vessel via the filtering membrane. In someembodiments, the method includes extracting embolic material through theinner sheath lumen while the embolic material capture element is in thefully deployed configuration.

In another aspect, an embolic material capture catheter includes afilter sheath and a filter assembly. The embolic material capturecatheter has a restrained insertion configuration and a deployedconfiguration. The filter sheath has an inner lumen and a filter sheathdistal end portion. The filter assembly is attached to the filter sheathdistal end portion. The filter assembly includes an outer scaffoldportion, an inner filter portion, and an intermediate portion. The outerscaffold portion has an outer scaffold proximal end portion and an outerscaffold distal end portion. The outer scaffold proximal end portion isattached to the filter sheath distal end portion. The outer scaffoldportion is configured to self-expand during reconfiguration of theembolic material capture catheter from the restrained insertionconfiguration to the deployed configuration for engagement with a bloodvessel inner surface. The inner filter portion has an inner filterproximal end portion and an inner filter distal end portion. The innerfilter proximal end portion is attached to the filter sheath distal endportion. The inner filter portion is configured to capture embolicmaterial from blood that flows through the inner filter portion. Theinner filter distal end portion is coupled with the outer scaffolddistal end portion via the intermediate portion. In many embodiments,the inner filter portion is separated from the outer scaffold portion byan intervening annular space in the deployed configuration. In someembodiments, the intermediate portion is configured to capture embolicmaterial from blood flowing through the intermediate portion. In someembodiments, the intermediate portion is nonporous. In many embodiments,the intermediate portion has a conical shape configured to direct bloodflow into the inner filter portion.

In some embodiments, the outer scaffold portion, the intermediateportion, and the inner filter portion are portions of an integrallyformed braided wire member. In such embodiments, the embolic materialcapture catheter can include a distal end sheet attached to theintermediate portion that is configured to block flow of embolicmaterial through the intermediate portion. In some embodiments, thedistal end sheet is nonporous. In some embodiments, the distal end sheethas a porosity adapted to filter embolic material out of blood flowingthrough the distal end sheet.

In many embodiments, the outer scaffold distal end portion is configuredfor atraumatic engagement of the blood vessel inner surface. Forexample, in many embodiments, the outer scaffold portion includesdistally extending loops of wires configured for atraumatic engagementof the blood vessel inner surface.

In another aspect, an embolic material capture catheter includes afilter sheath and a filter assembly. The embolic material capturecatheter has a restrained insertion configuration and a deployedconfiguration. The filter sheath has an inner lumen and a filter sheathdistal end portion. The filter assembly is attached to the filter sheathdistal end portion. The filter assembly includes an outer scaffoldportion and an inner filter portion. The outer scaffold portion has anouter scaffold proximal end portion and an outer scaffold distal endportion. The outer scaffold proximal end portion is attached to thefilter sheath distal end portion. The outer scaffold portion isconfigured to self-expand during reconfiguration of the embolic materialcapture catheter from the restrained insertion configuration to thedeployed configuration for engagement with a blood vessel inner surface.The inner filter portion has an inner filter proximal end portion. Theinner filter portion is attached to outer scaffold portion. The innerfilter portion is configured to capture embolic material from blood thatflows through the inner filter portion. In some embodiments, the innerfilter portion is attached to the outer scaffold portion along an entirelength of the outer scaffold portion.

For a fuller understanding of the nature and advantages of the presentinvention, reference should be made to the ensuing detailed descriptionand accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an embolic material capture catheter in an insertionconfiguration for insertion into and advancement through a blood vesselof a patient, in accordance with many embodiments.

FIG. 2 shows a distal portion of the embolic material capture catheterof FIG. 1 in the insertion configuration.

FIG. 3 shows an initial state of expansion of a middle portion of anembolic material capture element of the embolic material capturecatheter of FIG. 1 .

FIG. 4 shows an intermediate state of expansion of the middle portion ofthe embolic material capture element of the embolic material capturecatheter of FIG. 1 .

FIG. 5 shows a maximum state of expansion of the middle portion of theembolic material capture element of the embolic material capturecatheter of FIG. 1 .

FIG. 6 shows release of the distal end of the embolic material captureelement of the embolic material capture catheter of FIG. 1 via distaladvancement of a deployment cap relative to the configuration of FIG. 5.

FIG. 7 shows a distal portion of the embolic material capture catheterof FIG. 1 in the insertion configuration.

FIG. 8 shows a distal portion of the embolic material capture catheterof FIG. 1 with the deployment cap in the configuration of FIG. 6 .

FIG. 9 shows continued self-expansion of the embolic material captureelement of the embolic material capture catheter of FIG. 1 from theconfiguration of FIG. 6 .

FIG. 10 shows the embolic material capture element of the embolicmaterial capture catheter of FIG. 1 fully expanded.

FIG. 11 shows the embolic material capture catheter of FIG. 1 with theembolic material capture element fully deployed, dilator removed, andready for insertion of a treatment catheter to perform a surgical taskupstream of the deployed embolic material capture element.

FIG. 12 shows the embolic material capture catheter of FIG. 1 with theembolic material capture element fully deployed within a patient'saorta, dilator removed, and ready for insertion of a treatment catheterto perform a surgical task upstream of the deployed embolic materialcapture element.

FIG. 13 shows the embolic material capture catheter of FIG. 1 with theembolic material capture element fully deployed within a patient'saorta, dilator removed, and an aortic replacement valve deploymentcatheter inserted through the embolic material capture catheter andpositioned to deploy an aortic replacement valve.

FIG. 14 shows deployment of the aortic replacement valve from thedelivery configuration of FIG. 13 via expansion of an expandable memberof the aortic replacement valve deployment catheter.

FIG. 15 shows the embolic material capture catheter of FIG. 1 with theembolic material capture element in a captured configuration.

FIG. 16 is a simplified block diagram of acts of a method of deployingan embolic material capture element in a blood vessel, in accordancewith many embodiments.

FIG. 17 shows a shape of the embolic material capture catheter of FIG. 1while deployed within a vasculature of a patient.

FIG. 18 shows a first configuration of the embolic material captureelement of the embolic material capture catheter of FIG. 1 .

FIG. 19 shows a side view of the embolic material capture element ofFIG. 18 .

FIG. 20 shows a side cross-sectional view of the embolic materialcapture element of FIG. 18 .

FIG. 21 illustrates a process for fabricating the embolic materialcapture element of FIG. 18 .

FIG. 22 shows a close-up side view of a second configuration of theembolic material capture element of the embolic material capturecatheter of FIG. 1 .

FIG. 23 shows an isometric view of the embolic material capture elementof FIG. 22 .

FIG. 24 shows a side cross-sectional view of a third configuration ofthe embolic material capture element of the embolic material capturecatheter of FIG. 1 .

FIG. 25 shows an isometric view of the embolic material capture elementof FIG. 24 .

FIG. 26 is a simplified block diagram of acts of a method of fabricatingthe embolic material capture catheter of FIG. 1 .

FIG. 27 shows a side view of an embodiment the embolic material captureelement of FIG. 18 .

FIG. 28 shows a side cross-sectional view of the embodiment of theembolic material capture element of FIG. 27 .

FIG. 29 shows a side cross-sectional view of an embodiment of theembolic material capture element of FIG. 24 .

For a fuller understanding of the nature and advantages of the presentinvention, reference should be made to the ensuing detailed descriptionand accompanying drawings.

DETAILED DESCRIPTION

In the following description, various embodiments of the presentinvention will be described. For purposes of explanation, specificconfigurations and details are set forth in order to provide a thoroughunderstanding of the embodiments. However, it will also be apparent toone skilled in the art that the present invention may be practicedwithout the specific details. Furthermore, well-known features may beomitted or simplified in order not to obscure the embodiment beingdescribed.

Referring now to the drawings, in which like reference numeralsrepresent like parts throughout the several views, FIG. 1 shows anembolic material capture catheter 10 in an insertion configuration forinsertion into and advancement through a blood vessel of a patient, inaccordance with many embodiments. The catheter 10 includes an outersheath assembly 12, an inner sheath assembly 14, and a dilator assembly16. The outer sheath assembly 12 includes an outer sheath 18 and anouter sheath proximal end assembly 20 attached to the outer sheath 18.The outer sheath 18 is a flexible tube having an outer sheath lumenextending through the outer sheath 18. The outer sheath proximal endassembly 20 remains external to the patient and can be used to distallyadvance the outer sheath 18 through the blood vessel and proximallyretract the outer sheath 18 along and/or from the blood vessel. Theinner sheath assembly 14 includes an inner sheath 22, an inner sheathproximal end assembly 24 attached to the inner sheath 22, and an embolicmaterial capture element 36 (shown in FIG. 2 ) attached to the distalend of the inner sheath 22. The inner sheath 22 is a flexible tubehaving an inner sheath lumen extending through the inner sheath 22. Theinner sheath 22 is slidably disposed with the outer sheath lumen of theouter sheath 18. In many embodiments, the outer sheath proximal assembly20 includes a seal that interfaces with the outer surface of the innersheath 22 to inhibit and/or prevent escape of bodily fluid (e.g., blood)from an annular space between the inner sheath 22 and the outer sheath18. The inner sheath proximal end assembly 24 remains external to thepatient and can be used to distally advance the inner sheath 22 throughthe outer sheath 18 and the blood vessel and proximally retract theinner sheath 22 along and/or from the outer sheath 18 and the bloodvessel. The dilator assembly 16 includes a dilator sheath 26 and adilator cap assembly 28. The dilator sheath 26 is a flexible tube havinga dilator sheath lumen extending through the dilator sheath 26. Thedilator cap assembly 28 includes a dilator cap 30, a dilator shaft 32,and a dilator proximal member 34. The dilator cap 30 is attached to adistal end of the dilator shaft 32. The dilator proximal member 34 isattached to a proximal end of the dilator shaft 32. The dilator shaft 32extends through and is slidably disposed within the inner sheath lumenof the inner sheath 22. As described herein, a distal end portion of thedilator sheath 26 and the dilator cap 30 engage a distal end portion ofthe embolic material capture element 36 to restrain the distal endportion of the embolic material capture element 36 when the catheter 10is in the insertion configuration. By advancing the dilator cap assembly28 distally relative to the dilator sheath 26, the distal end portion ofthe embolic material capture element 36 can be released from engagementwith the distal end portion of the dilator sheath 26 and the dilator cap30, thereby allowing self-expansion of the distal end portion of theembolic material capture element 36 as described herein. In manyembodiments, the embolic material capture catheter 10 is adapted to bedeployed over a guidewire 106 (shown in FIG. 12 ). For example, thedilator assembly 16 can include a guide wire lumen that extends throughthe dilator assembly 16.

FIG. 2 shows a distal portion of the embolic material capture catheter10 in an insertion configuration. The illustrated portion of thecatheter 10 includes a distal end portion of the outer sheath 18, adistal end portion of the inner sheath 22 extending distally beyond thelumen of the outer sheath 18, the embolic material capture element 36 ina collapsed insertion configuration, a distal end portion of the dilatorsheath 26, and the dilator cap 30. In the illustrated insertionconfiguration, a distal end portion 38 of the embolic material captureelement 36 is trapped between a distal end portion of the dilator sheath26 and a proximal end portion of the dilator cap 30. With the distal endportion 38 of the embolic material capture element 36 restrained viaengagement with the dilator cap 30 and the distal end portion of thedilator sheath 26 and a proximal end portion 40 of the embolic materialcapture element 36 attached to the distal end of the inner sheath 22, asuitable position of the inner sheath 22 relative to the dilator cap 30can be maintained to retain the embolic material capture element 36 inthe collapsed insertion configuration. For example, in some embodiments,the embolic material capture element 36, in the illustrated collapsedinsertion configuration, is under axial tension induced via opposedaxial forces applied to the embolic material capture element 36 by thedilator assembly 16 and the inner sheath 22, respectively. In manyembodiments, the embolic material capture element 36 conforms to anouter surface of the dilator sheath 26 from the proximal end portion ofthe embolic material capture element 36 to the distal end portion of theembolic material capture element 36 when the embolic material captureelement 36 is in the insertion configuration. In many embodiments, thedilator cap 30 is configured to protect the vasculature during distaladvancement of the catheter 10 through the vasculature. In theillustrated configuration, the inner sheath 22 is positioned relative tothe outer sheath 18 so that the proximal end of the embolic materialcapture element 36 is disposed distal to the distal end of the outersheath 18 and maintained in the collapsed insertion configurationwithout the use of a sheath surrounding the embolic material captureelement 36.

FIG. 3 , FIG. 4 and FIG. 5 illustrate progressive expansion of theembolic material capture element 36 from the insertion configurationshown in FIG. 2 to the intermediate deployment configuration shown inFIG. 5 via distal advancement of the inner sheath 22 relative to thedilator assembly 16 while the distal end portion 38 of the embolicmaterial capture element 36 remains restrained by the dilator assembly16. As shown, a middle portion of the embolic material capture element36 expands radially from the insertion configuration to the intermediatedeployment configuration.

FIG. 6 shows release of the distal end 38 of the embolic materialcapture element 36 via advancement of the dilator cap assembly 28relative to the dilator sheath 26, thereby moving the dilator cap 30distally relative to the distal end of the dilator sheath 26. In manyembodiments, upon release of the distal end 38 of the embolic materialcapture element 36, the distal end 38 self-expands from the intermediatedeployment configuration of the embolic material capture element 36 tothe configuration shown in FIG. 9 and continues to self-expand to thefully deployed configuration of the embolic material capture element 36shown in FIG. 10 . In many embodiments, the embolic material captureelement 36 is made at least partially of a shape-memory material andself-expands from the insertion configuration to the fully deployedconfiguration in which an outer surface of the embolic material captureelement 36 engages an inner surface of the blood vessel.

FIG. 7 and FIG. 8 show close-up views of the distal portion of theembolic material capture catheter 10. FIG. 7 shows the distal portion ofthe embolic material capture catheter 10 in the insertion configuration.In the insertion configuration, the distal end portion 38 of the embolicmaterial capture element 36 is trapped within a proximal recess in thedilator cap 30 and retained in the proximal recess via the distal endportion of the dilator sheath 26. In the illustrated embodiment, thedistal end portion of the dilator sheath 26 includes annularlydistributed retention features 42 that protrude radially and areconfigured to locally engage the distal end portion 38 of the embolicmaterial capture element 36 to enhance retention of the distal endportion 38 within the proximal recess in the dilator cap 30. FIG. 8shows the distal portion of the embolic material capture catheter 10with the dilator cap 30 in the release configuration shown in FIG. 6 ,FIG. 9 , and FIG. 10 , in which the dilator cap 30 is disposed distal tothe distal end portion 38 of the embolic material capture element 36(not shown).

From the configuration shown in FIG. 10 , the dilator assembly 16 can beremoved through the inner sheath lumen of the inner sheath 22 to makethe inner sheath lumen available for insertion of a treatment catheterthrough inner sheath lumen of the inner sheath 22 to perform a surgicaltask upstream of the embolic material capture element 36 in the fullydeployed configuration. FIG. 11 shows the embolic material capturecatheter 10 with the embolic material capture element 36 in the fullydeployed configuration with the dilator assembly 16 removed. Because theinner sheath assembly 16 is advanced distally relative to the outersheath assembly 12 to deploy the embolic material capture element 36,the inner sheath proximal end assembly 24 can be in close proximity withthe outer sheath proximal end assembly 20 when the embolic materialcapture element 36 is in the fully deployed configuration, therebyenabling the use of existing length treatment catheters.

In some embodiments, the embolic material capture element 36 is composedof an outer support element and an inner filter element attached to theouter support element. The outer support element can include one or moremembers that radially expand into contact with the wall of a vesselalong which embolic material is blocked from traversing. The innerfilter element can include a filtering device or filtering membraneconfigured to prevent emboli of greater than a particular size frompassing through the filtering device or the filtering membrane. Theouter support element can be configured to provide a framework andstability for the inner filter element to function.

The embolic material capture catheter 10 can be configured for use inany suitable blood vessel and for use with any suitable treatmentcatheter. For example, FIG. 12 shows an embodiment of the embolicmaterial capture catheter 10 deployed within a patient's aorta 42 tocapture embolic material liberated during implantation of a prostheticaortic valve. FIG. 13 shows the embolic material capture catheter 10with an aortic replacement valve deployment catheter 100 insertedthrough the inner sheath lumen of the inner sheath 22 and positioned todeploy an aortic replacement valve 102. The replacement valve deploymentcatheter 100 includes an expandable member 104 that is expanded todeploy the valve 102. FIG. 13 illustrates the expandable member 104 (andthe prosthetic valve 102 mounted to the expandable member 104 in acollapsed configuration) positioned for implantation of the prostheticvalve 102 after being advance along a guide wire 106 and through theinner sheath lumen of the inner sheath 22. With the embolic materialcapture element 36 deployed downstream of the patient's native aorticvalve 108, the embolic material capture element 36 is positioned tocapture embolic material released during deployment of the prostheticaortic valve 102.

FIG. 14 illustrates deployment of the prosthetic valve 102 at theimplantation site via expansion of the expandable member 104. Theexpansion of the expandable member 104 expands the prosthetic aorticvalve 102 into its deployed configuration covering the native aorticvalve 108. The expandable member 104 can be expanded during rapid pacingof the patient's heart. Embolic material released during deployment ofthe prosthetic aortic valve 102 is captured by the embolic materialcapture element 36. In some embodiments, the embolic material capturecatheter 10 can be fluidly coupled with an external embolic materialremoval device operable to remove embolic material gathered by theembolic material capture element 36 from the patient. Followingimplantation of the prosthetic aortic valve 102, the replacement valvedeployment catheter 100 can be removed from the embolic materialprotection catheter 10 via proximal retraction through the inner sheathlumen of the inner sheath 22

In many embodiments, the embolic material capture catheter 10 can bereconfigured to capture the embolic material capture element 36 prior towithdrawal of the embolic material capture catheter 10 from the patient.For example, in the illustrated embodiment, the embolic material capturecatheter 10 can be reconfigured from the configuration shown in FIG. 11in which the embolic material capture element 36 is in the fullydeployed configuration to the configuration shown in FIG. 15 in whichthe embolic material capture element is in the captured configurationvia proximal retraction of the inner sheath assembly 14 relative to theouter sheath assembly 12, thereby pulling the embolic material captureelement 36 into the outer sheath lumen of the outer sheath 18.

FIG. 16 is a simplified block diagram of acts of a method 200 ofdeploying an embolic material capture element in a blood vessel, inaccordance with many embodiments. The method 200 can be practiced usingany suitable device or devices, including the embolic material capturecatheter 10 described herein. The method 200 can be used to provideembolic protection in conjunction with any suitable treatment, includingthe treatments indicated herein.

The method 200 includes constraining a proximal end portion of anembolic material capture element via attachment to a distal end portionof an inner sheath having an inner sheath lumen (act 202). For example,as illustrated in FIG. 2 , the proximal end 40 of the embolic materialcapture element 36 is attached to the distal end of the inner sheath 22in the embolic material capture catheter 10.

The method 200 further includes constraining a distal end portion of theembolic material capture element in an insertion configuration of theembolic material capture element and an intermediate deploymentconfiguration of the embolic material capture element via engagement ofthe distal end portion with a dilator assembly that extends through theinner sheath lumen (act 204). For example, in the insertionconfiguration illustrated in FIG. 2 and the intermediate deploymentconfiguration illustrated in FIG. 5 , the distal end portion 38 of theembolic material capture element 38 is constrained via engagement of thedistal end portion 38 with the dilator assembly 16, which extendsthrough the inner sheath lumen of the inner sheath 22.

The method 200 further includes advancing the embolic material captureelement in the insertion configuration through the blood vessel (act206). For example, act 206 can be accomplished via advancing the embolicmaterial capture catheter 10 through a blood vessel in either of theinsertion configurations shown in FIG. 1 and FIG. 2 .

The method 200 further includes reconfiguring the embolic materialcapture element from the insertion configuration to the intermediatedeployment configuration by expanding a middle portion of the embolicmaterial capture element disposed between the proximal end portion ofthe embolic material capture element and the distal end portion of theembolic material capture element via distal advancement of the innersheath toward the distal end portion of the embolic material captureelement constrained by the dilator assembly (act 208). For example, act208 can be accomplished via reconfiguring the embolic material capturecatheter 10 from the insertion configuration illustrated in FIG. 2 tothe intermediate deployment configuration illustrated in FIG. 5 asdescribed herein.

The method 200 further includes reconfiguring the embolic materialcapture element from the intermediate deployment configuration to thefully deployed configuration via reconfiguration of the dilator assemblyto release the distal end portion of the embolic material captureelement from engagement with the dilator assembly and self-expansion ofthe distal end portion of the embolic material capture element (act210). For example, act 210 can be accomplished via reconfiguring theembolic material capture catheter 10 from the intermediate deploymentconfiguration illustrated in FIG. 5 to the fully deployed configurationillustrated in FIG. 10 as described herein.

FIG. 17 shows a shape of the embolic material capture catheter 10 whiledeployed within a vasculature of a patient. In many embodiments, theembolic material capture element 36 has a flexibility so as to have adeployed shape in which the distal end portion 38 conforms to the innersurface of the blood vessel (e.g., the aorta 42) and conform to theshape of the blood vessel. For example, in many embodiments, the embolicmaterial capture element 36 is configured to conform to the shape (e.g.,curvature) of the blood vessel between the distal end portion 38 and theproximal end portion 40 (e.g., to the curvature of the aorta 42 asillustrated in FIG. 17 ).

Embolic Material Capture Element Configurations

The embolic material capture element 36 can have any suitableconfiguration. For example, FIG. 18 shows a first configuration 36 a ofthe embolic material capture element 36. The first configuration 36 a ofthe embolic material capture element 36 includes an outer scaffold 44,an inner filter 46, an a connection cone 48 that connects a distal endof the inner filter 46 to the distal end of the outer scaffold 44. FIG.19 shows a side view of the first configuration 36 a the embolicmaterial capture element 36. FIG. 20 shows a side cross-sectional viewof the first configuration 36 a of the embolic material capture element36.

The outer scaffold 44 includes one or more inter-braidedhelically-shaped lengths of a suitable wire 44 w (e.g., 0.006 to 0.010inch diameter wire made from a suitable nickel-titanium shape-memoryalloy). In many embodiments, strands of the wire 44 w are alternatelywoven (e.g., passed over and then under) crossing portions of thestrands of the wire 44 w. From the insertion configuration shown in FIG.2 to the fully deployed configuration shown in FIG. 18 , a pitch betweenadjacent locations on the wire 44 w decreases from a suitable initialpitch to a suitable deployed pitch (DP) and the diameter of the outerscaffold 44 increases from a suitable insertion configuration diameterto a suitable fully deployed configuration diameter, thereby producing acorresponding decrease in the length of the outer scaffold 44. The wire44 w of the outer scaffold 44 has a shape memory such that the outerscaffold 44 automatically reconfigures from the insertion configurationto the fully deployed configuration in response to the distaladvancement of the inner sheath 22 and the release of the distal endportion 38 of the first configuration 36 a of the embolic materialcapture element 36. Upon retraction of the first configuration 36 a ofthe embolic material capture element 36 into the outer sheath 18, thepitch between adjacent locations on the wire 44 w increases and thediameter of the outer scaffold 44 decreases, thereby producing acorresponding increase in the length of the outer scaffold 44. In theillustrated embodiment, the outer scaffold 44 has an atraumatic leadingedge 50 formed by loops of the wire 44 w. In some embodiments, the outerscaffold 44 includes capture loops that are engaged with the distal endportion of the dilator sheath 26 and the proximal end portion of thedilator cap 30 while the embolic material capture element 36 is in theinsertion configuration. In some embodiments, the maximum expandeddiameter of the embolic material capture element 36 is sized to ensureengagement with a patient's aortic arch.

In many embodiments, the inner filter 46 has a suitable porosity thatprovides for capture of embolic material by the inner filter 46 whileaccommodating blood flow through the inner filter 46. The inner filter46 can be made from any suitable material. For example, in someembodiments, the inner filter 46 includes a helically-braidedpolyethylene terephthalate (PET) filter. In some embodiments, the innerfilter 46 includes a helically-braided polymer filter made from asuitable polymer yarn such as ultra-high-molecular-weight polyethylene(UHMWPE), PET, nylon, polypropylene, polytetrafluoroethylene (PTFE), andliquid crystal polymer (LCP). In some embodiments, the inner filter 46includes a laser cut polymer filter made from a suitable polymermaterial (e.g., elastomeric materials such as silicones, polyurethanesand co-polymers). In some embodiments, the inner filter 46 includes awoven textile filter with a diameter less than or equal to the braidedouter scaffold 44 with target porosity to capture embolic material andallow for blood flow through the inner filter 46. Such a woven textilefilter can be made from a suitable polymer yarn such as UHMWPE, PET,nylon, polypropylene, PTFE, and LCP. The inner filter 46 can have anysuitable configuration. For example, in many embodiments, the innerfilter 46 can have an outer diameter in the fully deployed configurationless than or equal to the inner diameter of the outer scaffold 44 in thefully deployed configuration. In many embodiments, the inner filter 46has a longitudinal length and/or longitudinal flexibility thataccommodates the change in length of the outer scaffold 44 between theinsertion configuration and the fully deployed configuration.

The connection cone 48 connects the distal end of the inner filter 46 tothe distal end of the outer scaffold 44. In the illustrated embodiment,the diameter of the distal end of the connection cone 48 is larger thanthe diameter of the proximal end of the connection cone 48. In manyembodiments, the connection cone 48 has a shape (e.g., conical) thatprovides for a smooth transition for blood flow into the distal openingof the inner filter 46. The connection cone 48 can be made from anysuitable material. For example, the connection cone 48 can be formedfrom a suitable polymer sheet. The connection cone 48 can be attached tothe outer scaffold 44 and the inner filter 46 using any suitableapproach. For example, a distal end portion of the connection cone 48can be laminated to a corresponding distal end portion of the outerscaffold 44; a proximal end portion of the connection cone 48 can belaminated to a corresponding distal end portion of the inner filter 46.The connection cone 48 can be nonporous or have a suitable porosity thatprovides for capture of embolic material by the connection cone 48 whileaccommodating blood flow through the connection cone 48. For example, asuitable porous connection cone 48 can be formed from a laser cutpolymer sheet.

The inner filter 46 can be fabricated using any suitable approach. Forexample, the inner filter 46 can be manufactured as a stand-alone singlebraid. As another example, the inner filter 46 can be cut from a longersection of tubing that is braided to meet the target porosity of theinner filter 46. In many embodiments, the maximum diameter of the innerfilter 46 is less than the deployed diameter of the outer scaffold 44and the minimum diameter of the inner filter 46 is larger than thedelivery catheter for the prosthetic valve.

The first configuration 36 a of the embolic material capture element 36can be assembled using any suitable approach. For example, referring toFIG. 21 , a mandrel 110 having a first cylindrical section 112, aconical section 114, and a second cylindrical section 116 can beemployed to assemble the first configuration 36 a of the embolicmaterial capture element 36. The mandrel 110 can be made from anysuitable material (e.g., a suitable metal or plastic). The firstcylindrical section 112 has a diameter (dl) that is selected so that thefirst cylindrical section 112 can be inserted through the inner filter46 as illustrated to restrain the inner filter 46 during attachment ofthe inner filter 46 to the connection cone 48. With the inner filter 46in the illustrated position on the first cylindrical section 112, theconnection cone 48 can be formed onto, or attached to, the inner filter46 using any suitable approach. For example, in some embodiments, theconnection cone 48 is formed on the mandrel 110 (e.g., onto the conicalsection 114, a distal end portion 118 of the inner filter 46, and aproximal end portion 120 of the second cylindrical section 116) byapplying a suitable material (e.g., a suitable polymer material) viadipping or spraying. In many embodiments, the connection cone 48includes a proximal cylindrical portion 122 that overlaps the distal endportion 118 of the inner filter 46.

The connection cone 48 can alternatively be separately formed. Forexample, a section of polymer tubing can be attached to the distal endportion 118 of the inner filter 46 via dipping, spraying, or heatsetting. The resulting assembly can be placed into a mold and thesection of the polymer tubing molded into the shape of the connectioncone 48 using any suitable approach (e.g., similar to how some medicalcatheter balloons are blow molded). The distal end portion of theresulting connection cone 48 can be trimmed to a desired shape after itis removed from the mold. In many embodiments, the proximal cylindricalportion 122 of the connection cone 48 overlaps the distal end portion118 of the inner filter 46. In embodiments where the connection cone 48is porous, the connection cone 48 can be laser cut after being formed toadd porosity.

With the inner filter 46 attached to the connection cone 48, a distalend portion 124 of the outer scaffold 44 can be attached to a distal endportion 126 of the connection cone 48. The connection cone 48 can beplaced inside of the outer scaffold 44 and the distal edges of theconnection cone 48 and outer scaffold 44 can be aligned. If the outerscaffold 44 includes capture loops that are engaged with the distal endportion of the dilator sheath 26 and the proximal end portion of thedilator cap 30 while the embolic material capture element 36 is in theinsertion configuration, the capture loops can be masked off. The distalend portion 126 of the connection cone 48 can be attached to the distalend portion 124 of the outer scaffold 44 over a desired connectionlength using any suitable approach, for example, via heating to bond thedistal end portions, via dipping in a suitable bonding agent to bond thedistal end portions, or spraying of a suitable bonding agent to bond thedistal end portions 124, 126. The completed first configuration 36 a ofthe embolic material capture element 36 can then be removed from themandrel 110.

FIG. 22 shows a close-up side view of a second configuration 36 b of theembolic material capture element 36. The second configuration 36 b ofthe embolic material capture element 36 includes the outer scaffold 44(which is described above) and an inner filter 52 attached to andsupported by the outer scaffold 44. FIG. 23 shows an isometric view ofthe second configuration 36 b of the embolic material capture element36.

In many embodiments, the inner filter 52 has a suitable porosity thatprovides for capture of embolic material by the inner filter 52 whileaccommodating blood flow through the inner filter 52. The inner filter52 can be made from any suitable material. For example, the inner filter52 can be made from a porous polymer sheet. The inner filter 52 can haveany suitable configuration. For example, in many embodiments, the innerfilter 52 has an outer diameter in the fully deployed configurationequal to the inner diameter of the outer scaffold 44 in the fullydeployed configuration. In many embodiments, the inner filter 52 has alongitudinal length and/or longitudinal flexibility that accommodatesthe change in length of the outer scaffold 44 between the insertionconfiguration and the fully deployed configuration. The inner filter 52can be attached to the outer scaffold 44 using any suitable approach.

FIG. 24 shows a side cross-sectional view of a third configuration 36 cof the embolic material capture element 36. The third configuration 36 cof the embolic material capture element 36 includes a helically-braidedshape memory alloy tube 54 and a distal end sheet 56. The braided shapememory alloy tube 54 is folded inside itself so as to have an outer tubeportion 58, an inner tube portion 60, and a distal end portion 62disposed between the outer tube portion 58 and the inner tube portion60. The outer tube portion 58 can have any suitable diameter in thefully deployed configuration for use within a target blood vessel. Forexample, the outer tube portion 58 can have an outer diameter in thefully deployed configuration compatible with a target aorta anatomy. Inmany embodiments, the braided shape memory alloy tube 54 has a braidedwire construction similar to the outer scaffold 44. In many embodiments,the porosity of the outer tube portion 58 in the fully deployedconfiguration is higher than the porosity of inner tube portion 60. Inmany embodiments, the diameter and/or the braid count of the inner tubeportion 60 are selected to provide a suitable porosity for embolicmaterial capture, for example, less than or equal to 150 microns. Thedistal end portion 62 can have a porosity that varies from therelatively higher porosity of the outer tube portion 58 to the porosityof the inner tube portion 60. The porosity of the outer tube portion 58in the fully deployed configuration can be higher than the porosity ofinner tube portion 60 due to the difference in diameters of the tubeportions 58, 60. The maximum porosity of the braid can be calculatedwhen the angle is at 90 degrees between the strands. The inner tubeportion 60 can have a lower porosity for braid angles of the inner tubeportion 60 that are greater than and less than 90 degrees, therebyproducing diamond shape openings between the strands. The inner diameterof the inner tube portion 60 can be heat set to be large enough toaccommodate the treatment catheter 100 and small enough so that thediamond shape of the crossing braid members has a porosity less than orequal to the target porosity. The distal end sheet 56 is attached to thedistal end portion 62. The distal end sheet 56 can be nonporous or havea suitable porosity that provides for capture of embolic material by thedistal end sheet 56 while accommodating blood flow through the distalend sheet 56. The distal end sheet 56 can be made from any suitablematerial. For example, the distal end sheet 56 can be formed from asolid polymer sheet or a porous laser cut polymer sheet. The distal endsheet 56 can be attached to the distal end portion 62 using any suitableapproach. For example, the distal end sheet 56 can be laminated to thedistal end portion 62 using any suitable approach. The distal end sheet56 ensures that embolic material is prevented from passing through thedistal end portion 62 and is funneled into the inner tube portion 54.FIG. 25 shows an isometric view of the third configuration 36 c of theembolic material capture element 36.

FIG. 26 shows a simplified schematic diagram of acts of a method 300 forfabricating embodiments the embolic material capture catheter 10. Acts302, 304, and 306 are directed to fabricating the first configuration 36a of the embolic material capture element 36. Acts 308, 310, and 312 aredirected to assembly of embodiments the embolic material capturecatheter 10.

In act 302, the outer scaffold 44 and the inner filter 46 are fabricatedto length using any suitable approach. For example, in many embodiments,the outer scaffold 44 is fabricated by helically winding andinter-braiding a suitable number of strands (e.g., 24-48 strands) of asuitable diameter (e.g., 0.006 to 0.010 inch) shape-memory wire (e.g.,made from a suitable nickel-titanium shape memory alloy) at a suitablelongitudinal pitch. In many embodiments, the strands of the wire 44 ware helically-winded and inter-braided so that no ends of the strandsare disposed at the distal end of the outer scaffold 44 to enhance thesmoothness of the distal end of the outer scaffold 44. In manyembodiments, the outer scaffold 44 is formed to have a fully-deployedconfiguration having a distal end external diameter a suitable amountlarger than the diameter of the target blood vessel (e.g., aorta) sothat, when deployed in the target blood vessel, the outer scaffold 44will expand into engagement with the inner surface of the target bloodvessel and exert a suitable radial force on the target blood vessel tomaintain the position of the embolic material capture element 36 withinthe target blood vessel. In many embodiments, the inner filter 46 isfabricated by helically winding and inter-braiding a suitable number ofstrands (e.g., 288 strands) of a suitable diameter wire (e.g., 0.002inch) of a suitable material (e.g., PET) at a suitable pitch. In manyembodiments, the inner filter 46 is formed to have a fully-deployedconfiguration having a distal end external diameter a suitable amountsmaller than the diameter of the target blood vessel (e.g., aorta) sothat, when deployed in the target blood vessel, the inner filter 46 willbe separated from the outer scaffold 44 by a suitably-sized annularspace that accommodates flow of blood through the inner filter 46. Inmany embodiments, the outer scaffold 44 and the inner filter 46 areconfigured to longitudinally expand by substantially the same distancewhen reconfigured from the deployed configuration to the constrainedinsertion configuration, and to longitudinally contract by substantiallythe same distance when deployed from the constrained insertionconfiguration to the deployed configuration. The longitudinalexpansion/contraction characteristics each of the outer scaffold 44 andthe inner filter 46 can matched via suitable selection of parameters ofthe respective helical structures, such as longitudinal pitch and strandcount, in view of the respective deployed diameters and the respectiveconstrained insertion diameters. In act 304, the connection cone 48 iscreated on the end of the inner filter 46 using any suitable approach,such as the approach described herein with reference to FIG. 21 . In act306, the distal end of the connection cone 48 is connected to the distalend of the outer scaffold using any suitable approach, such as theapproach described herein with reference to FIG. 21 .

In act 308, the proximal end of the embolic material capture element 36is attached to the distal end of the inner sheath 22 using any suitableapproach. For example, the embolic material capture element 36 can beattached to the inner sheath 22 during fabrication of the inner sheath22 or attached to the inner sheath 22 (e.g., to the inner diameterand/or to the outer diameter of the inner sheath 22) after the innersheath 22 is fabricated. In some embodiments, the inner sheath 22includes an inner liner (e.g., made from PTFE), a structural braid orcoil (e.g., made from stainless steel, Nitinol, or monofilament), and anouter member polymer jacket (e.g., made from polyether block amide(PEBA), or nylon). The embolic material capture element 36 can be joinedto the inner sheath 22 during fabrication of the inner sheath bydisposing a proximal end portion of the embolic material capture elementbetween the inner liner and the structural braid or coil of the innersheath 22 or between the structural braid or coil and the outer memberpolymer jacket. The embolic material capture element 36 can be attachedto the inner sheath 22 after fabrication of the inner sheath via apolymer sleeve (e.g., made from PEBA or nylon) to sandwich the proximalend portion of the inner filter 46 between the OD or ID of the distalend portion of the inner sheath 22 and the polymer sleeve. In act 310,the outer sheath 18 is attached to the outer sheath proximal endassembly 20 and the inner sheath 22 is attached to the inner sheathproximal end assembly 24. In act 312, Luers and tubing are attached tothe proximal end assemblies 20, 24.

FIG. 27 shows a side view of an embodiment 36 a-1 of the embolicmaterial capture element 36 a in the fully deployed configuration. FIG.28 shows a side cross-sectional view of the embolic material captureelement 36 a-1 in the fully deployed configuration. In the fullydeployed configuration, the embolic material capture element 36 a-1 hasa stepped outer diametrical profile configured to enhance deploymentfrom the insertion configuration to the fully deployed configuration bysubstantially isolating contact between the outer scaffold 44 and theblood vessel to a distal end portion 64 of the embolic material captureelement 36 a-1. In the fully deployed configuration, a middle portion 66of the embolic material capture element 36 a-1 has a middle portionexternal diameter 68, and the distal end portion 64 has a distal endportion external diameter 70. In many embodiments, the distal endportion external diameter 70 is sized to provide a suitable amount ofengagement with a target blood vessel. For example, the distal endportion external diameter 70 can be sized so that, in the fully deployedconfiguration, the distal end portion external diameter 70 would be asuitable increment larger than the inner diameter of the target bloodvessel (e.g., aorta) so that the distal end portion 64 would exert asuitable interface pressure onto the target blood vessel when deployedin the target blood vessel. In many embodiments, the middle portionexternal diameter 68 is a suitably smaller than the inner diameter ofthe target blood vessel so that there is an annular clearance betweenthe middle portion 66 and the inner wall of the target blood vessel toaccommodate lengthwise contraction of the embolic material captureelement 36 a-1 during deployment from the insertion configuration to thefully deployed configuration by substantially isolating contact betweenthe outer scaffold 44 and the blood vessel to the distal end portion 64.The annular clearance between the middle portion 66 and the inner wallof the target blood vessel serves to avoid interaction between theportion of the embolic material capture element 36 a-1 proximal to thedistal end portion 64 that might inhibit the contraction of the embolicmaterial capture element 36 a-1 during deployment from the insertionconfiguration to the fully deployed configuration. The middle portionexternal diameter 68, in the fully deployed configuration, can be anysuitable amount smaller than the inner diameter of the target bloodvessel or the distal end portion external diameter 70. For example, inthe illustrated embodiment, the middle portion external diameter 68 isabout 50 percent of the distal end portion external diameter 70.

The illustrated embodiment of the embolic material capture element 36a-1 includes a proximal connection cone 47 that connects the proximalend of the inner filter 46 to the distal end of the inner sheath 22. Inmany embodiments, the proximal connection cone 47 has a shape (e.g.,conical) that provides for a smooth transition between the proximal endof the inner filter 46 and the distal end of the inner sheath 22. Theproximal connection cone 47 can be made from any suitable material. Forexample, the proximal connection cone 47 can be formed from a suitablepolymer sheet. The proximal connection cone 47 can be attached to theinner filter 46 and the inner sheath 22 using any suitable approach. Forexample, a distal end portion of the proximal connection cone 47 can belaminated to a corresponding proximal end portion of the inner filter46; a proximal end portion of the proximal connection cone 47 can beattached to the distal end portion of the inner sheath 22. The proximalconnection cone 47 can be nonporous or have a suitable porosity thatprovides for capture of embolic material by the proximal connection cone47 while accommodating blood flow through the proximal connection cone47. For example, a suitable porous proximal connection cone 47 can beformed from a laser cut polymer sheet.

In some embodiments of the embolic material capture element 36 a-1, eachof the connection cone 48 and/or the proximal connection cone 47 has arespective flexibility that accommodates differences between the amountof contraction of the outer scaffold 44 and the inner filter 46 duringdeployment from the insertion configuration to the fully deployedconfiguration. For example, each of the connection cone 48 and/or theproximal connection cone 47 can have a respective flexibility thataccommodates changes in the longitudinal length of the connection cone48 and/or the proximal connection cone 47 between the fully deployedconfiguration and the insertion configuration so as to accommodatedifferences between the amount of contraction of the outer scaffold 44and the inner filter 46 during deployment from the insertionconfiguration to the fully deployed configuration.

FIG. 29 shows a side cross-sectional view of an embodiment 36 c-1 of theembolic material capture element 36 c in the fully deployedconfiguration. In the fully deployed configuration, the embolic materialcapture element 36 c-1 has a stepped outer diametrical profileconfigured to enhance deployment from the insertion configuration to thefully deployed configuration by substantially isolating contact betweenthe braided shape memory alloy tube 54 and the blood vessel to a distalend portion 72 of the embolic material capture element 36 c-1. In thefully deployed configuration, a middle portion 74 of the embolicmaterial capture element 36 c-1 has a middle portion external diameter76, and the distal end portion 72 has a distal end portion externaldiameter 78. In many embodiments, the distal end portion externaldiameter 78 is sized to provide a suitable amount of engagement with atarget blood vessel. For example, the distal end portion externaldiameter 78 can be sized so that, in the fully deployed configuration,the distal end portion external diameter 78 would be a suitableincrement larger than the inner diameter of a target blood vessel (e.g.,aorta) so that the distal end portion 72 would exert a suitableinterface pressure onto the target blood vessel when deployed in thetarget blood vessel. In many embodiments, the middle portion externaldiameter 76 is a suitably smaller than the inner diameter of the targetblood vessel so that there is an annular clearance between the middleportion 74 and the inner wall of the target blood vessel to accommodatelengthwise contraction of the embolic material capture element 36 c-1during deployment from the insertion configuration to the fully deployedconfiguration by substantially isolating contact between the braidedshape memory alloy tube 54 and the blood vessel to the distal endportion 72. The annular clearance between the middle portion 74 and theinner wall of the target blood vessel serves to avoid interactionbetween the portion of the embolic material capture element 36 c-1proximal to the distal end portion 72 that might inhibit the contractionof the embolic material capture element 36 c-1 during deployment fromthe insertion configuration to the fully deployed configuration. Themiddle portion external diameter 76, in the fully deployedconfiguration, can be any suitable amount smaller than the innerdiameter of the target blood vessel or the distal end portion externaldiameter 78. For example, in the illustrated embodiment, the middleportion external diameter 76 is about 50 percent of the distal endportion external diameter 78.

The devices and methods described herein are expected to producesubstantial benefits in the way of substantially increased safety andefficacy of surgical treatments with a high likelihood of generation ofembolic material, such as aortic valve replacement. As a result, suchsurgical treatments may be performed on a substantially increased numberof patients with improve outcomes and reduce recovery times.Specifically, there will be less embolic material conveyed within thecirculation system, thereby lowering the incidence of clinical stroke,subclinical stroke, silent cerebral embolization, renal embolization,mesenteric embolization, and peripheral embolization and each of theassociated clinical syndromes.

The embolic material capture catheter 10 is suitable for use inprocedures involving covered or uncovered stenting of arteries forcapture and extraction of embolic material that may be liberated duringtheir implantation for the treatment of aneurysms, dissections, stenosisor thrombus. The embolic material capture catheter 10 is suitable forprevention of injury resulting from embolic events occurring duringballoon aortic valvuloplasty. The embolic material capture catheter 10is suitable for prevention of tissue injury resulting from theperformance of mitral balloon valvuloplasty or replacement. In the caseof mitral procedures, the embolic protection provided by the embolicmaterial capture catheter 10 may be separate from a delivery catheter.In this situation there may be a separate transvenous or transapicalimplantation system of sheaths and catheters for valve delivery anddeployment and the embolic material capture catheter 10 can be deployedin the ascending aorta for capture and elimination of the materialliberated from the mitral valve manipulation.

Other variations are within the spirit of the present invention. Forexample, the configurations 36 a, 36 b, 36 c of the embolic materialcapture element 36 described herein can be deployed between an insertionconfiguration and a deployed configuration via relative movement of arestraining outer sheath without having the distal end of the embolicmaterial capture element 36 separately constrained and subsequentlyreleased. For example, in some embodiments, an embolic material capturecatheter for insertion into and advancement through a blood vessel of apatient includes the outer sheath assembly 12 and the inner sheathassembly 14, and does not include the dilator assembly 16. In suchembodiments, the embolic material capture element 36 can be restrainedin the insertion configuration via the outer sheath 18 during distaladvancement through a blood vessel of a patient and then released forself-expansion from the insertion configuration to the deployedconfiguration via proximal retraction of the outer sheath assembly 12relative to the inner sheath assembly 14. Such embodiments of an embolicmaterial capture catheter (which do not include the dilator assembly 16)may be considerably shorter than embodiments that include the dilatorassembly 26 and may be particularly suited for insertion via non-femoralaccess (e.g., trans-aortic access, trans-innominate access, ortrans-subclavian access). Thus, while the invention is susceptible tovarious modifications and alternative constructions, certain illustratedembodiments thereof are shown in the drawings and have been describedabove in detail. It should be understood, however, that there is nointention to limit the invention to the specific form or formsdisclosed, but on the contrary, the intention is to cover allmodifications, alternative constructions, and equivalents falling withinthe spirit and scope of the invention, as defined in the appendedclaims.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. The term “connected” is to beconstrued as partly or wholly contained within, attached to, or joinedtogether, even if there is something intervening. Recitation of rangesof values herein are merely intended to serve as a shorthand method ofreferring individually to each separate value falling within the range,unless otherwise indicated herein, and each separate value isincorporated into the specification as if it were individually recitedherein. All methods described herein can be performed in any suitableorder unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate embodiments of the invention and does not pose a limitationon the scope of the invention unless otherwise claimed. No language inthe specification should be construed as indicating any non-claimedelement as essential to the practice of the invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

Examples of the embodiments of the present disclosure can be describedin view of the following clauses:

Clause 1. An embolic material capture catheter comprising: an outersheath defining an outer sheath lumen; an inner sheath slidably disposedin the outer sheath lumen and defining an inner sheath lumen; an embolicmaterial capture element having a proximal end portion and a distal endportion, the proximal end portion being attached to a distal end portionof the inner sheath, the embolic material capture element having aninsertion configuration, an intermediate deployment configuration, and afully deployed configuration; the embolic material capture element beingadapted to, in the fully deployed configuration, interface with an innersurface of a blood vessel; the embolic material capture element beingadapted to block flow of embolic material through the blood vessel pastthe embolic material capture element; and a dilator assembly including adilator sheath and a deployment cap assembly, the dilator sheath beingslidably disposed in the inner sheath lumen and defining a dilatorsheath lumen, the deployment cap assembly being slidably disposed in thedilator sheath lumen, wherein: a distal end portion of the embolicmaterial capture element is restrained in the insertion configurationand the intermediate deployment configuration by the dilator assembly, amiddle portion of the embolic material capture element expands radiallyfrom the insertion configuration to the intermediate deploymentconfiguration via distal advancement of the inner sheath towards thedistal end portion of the embolic material capture element restrained bythe dilator assembly, the distal end portion of the embolic materialcapture element expands radially from the intermediate deploymentconfiguration to the fully deployed configuration in response to releaseof the distal end portion of the embolic material capture element by thedilator assembly via distal advancement of the deployment cap assemblyrelative to the dilator sheath, and the dilator assembly is removablefrom the inner sheath lumen while the embolic material capture elementis in the fully deployed configuration via proximal retraction of thedilator assembly relative to the inner sheath.

Clause 2. The embolic material capture catheter of clause 1, wherein theembolic material capture element is reconfigurable from the fullydeployed configuration to a captured configuration in which the embolicmaterial capture element is disposed in the outer sheath lumen viaproximal retraction of the inner sheath relative to the outer sheath.

Clause 3. The embolic material capture catheter of any preceding clause,wherein the embolic material capture element conforms to an outersurface of the dilator sheath from the proximal end portion of theembolic material capture element to the distal end portion of theembolic material capture element when the embolic material captureelement is in the insertion configuration.

Clause 4. The embolic material capture catheter of any preceding clause,wherein: the embolic material capture element has an outer surface thatextends between the proximal end portion of the embolic material captureelement and the distal end portion of the embolic material captureelement; and the outer surface of the embolic material capture elementis disposable distal to the outer sheath with the embolic materialcapture element in the insertion configuration.

Clause 5. The embolic material capture catheter of any preceding clause,wherein the embolic material capture element comprises a shape-memorymaterial.

Clause 6. The embolic material capture catheter of clause 5, wherein theembolic material capture element is retained in the insertionconfiguration at least partially via axial tension imparted into theembolic material capture element via the dilator assembly.

Clause 7. The embolic material capture catheter of any preceding clause,wherein: the inner sheath accommodates insertion of a treatment catheterinto the inner sheath lumen and advancement of a distal portion of thetreatment catheter to a position distal to the distal end portion of theembolic material capture element in the fully deployed configuration;and the distal end portion of the treatment catheter is adapted toaccomplish a surgical task.

Clause 8. The embolic material capture catheter of clause 7, wherein:the embolic material capture element is adapted to, in the fullydeployed configuration, interface with a patient's aorta andsubstantially block flow of embolic material through the patient's aortapast the embolic material capture element; and the treatment catheter isadapted to deploy a prosthetic aortic valve.

Clause 9. The embolic material capture catheter of any preceding clause,wherein the embolic material capture element comprises a filteringmembrane adapted to filter embolic material from blood flowing throughthe filtering membrane.

Clause 10. The embolic material capture catheter of any precedingclause, adapted to be coupled with an embolic material extraction deviceoperable to draw embolic material through the inner sheath lumen whilethe embolic material capture element is in the fully deployedconfiguration.

Clause 11. The embolic material capture catheter of any precedingclause, wherein the embolic material capture element comprises an outersupport element and an inner filter element attached to the outersupport element, the outer support element including one or more membersthat radially expand into contact with the wall of a vessel along whichembolic material is blocked from traversing, the inner filter elementbeing configured to prevent emboli of greater than a particular sizefrom passing through the inner filter element.

Clause 12. The embolic material capture catheter of any precedingclause, wherein the embolic material capture element comprises an outerscaffold portion, an inner filter portion, and an intermediate portion;the outer scaffold portion having an outer scaffold proximal end portionand an outer scaffold distal end portion; the outer scaffold proximalend portion being attached to the filter sheath distal end portion; theouter scaffold portion being configured to self-expand duringreconfiguration of the embolic material capture catheter from therestrained insertion configuration to the deployed configuration forengagement with a blood vessel inner surface; the inner filter portionhaving an inner filter proximal end portion and an inner filter distalend portion; the inner filter proximal end portion being attached to thefilter sheath distal end portion; the inner filter portion beingconfigured to capture embolic material from blood that flows through theinner filter portion; the inner filter distal end portion being coupledwith the outer scaffold distal end portion via the intermediate portion.

Clause 13. The embolic material capture catheter of clause 12, whereinthe inner filter portion is separated from the outer scaffold portion byan intervening annular space in the deployed configuration.

Clause 14. The embolic material capture catheter of clause 13, whereinthe intermediate portion is configured to capture embolic material fromblood flowing through the intermediate portion.

Clause 15. The embolic material capture catheter of clause 13, whereinthe intermediate portion is nonporous.

Clause 16. The embolic material capture catheter of any one of clause 13through clause 15, wherein the intermediate portion has a conical shapeconfigured to direct blood flow into the inner filter portion.

Clause 17. The embolic material capture catheter of any one of clause 13through clause 16, wherein the outer scaffold portion, the intermediateportion, and the inner filter portion are portions of an integrallyformed braided wire member.

Clause 18. The embolic material capture catheter of clause 17, furthercomprising a distal end sheet attached to the intermediate portion, thedistal end sheet being configured to block flow of embolic materialthrough the intermediate portion.

Clause 19. The embolic material capture catheter of clause 18, whereinthe distal end sheet is nonporous.

Clause 20. The embolic material capture catheter of clause 18, whereinthe distal end sheet has a porosity adapted to filter embolic materialout of blood flowing through the distal end sheet.

Clause 21. The embolic material capture catheter of any one of clause 13through clause 20, wherein the outer scaffold portion comprises distallyextending loops of wires configured for atraumatic engagement of theblood vessel inner surface.

Clause 22. A method of deploying an embolic material capture element ina blood vessel, the method comprising: constraining a proximal endportion of an embolic material capture element via attachment to adistal end portion of an inner sheath having an inner sheath lumen;constraining a distal end portion of the embolic material captureelement in an insertion configuration of the embolic material captureelement and an intermediate deployment configuration of the embolicmaterial capture element via engagement of the distal end portion of theembolic material capture element with a dilator assembly that extendsthrough the inner sheath lumen; advancing the embolic material captureelement in the insertion configuration through the blood vessel;reconfiguring the embolic material capture element from the insertionconfiguration to the intermediate deployment configuration by expandinga middle portion of the embolic material capture element disposedbetween the proximal end portion of the embolic material capture elementand the distal end portion of the embolic material capture element viadistal advancement of the inner sheath toward the distal end portion ofthe embolic material capture element constrained by the dilatorassembly; and reconfiguring the embolic material capture element fromthe intermediate deployment configuration to the fully deployedconfiguration via reconfiguration of the dilator assembly to release thedistal end portion of the embolic material capture element fromengagement with the dilator assembly and self-expansion of the distalend portion of the embolic material capture element.

Clause 23. The method of clause 22, further comprising reconfiguring theembolic material capture element from the fully deployed configurationto a captured configuration via proximal retraction of the inner sheathrelative to an outer sheath to retract the embolic material captureelement within an outer sheath lumen of the outer sheath.

Clause 24. The method of any one of clause 22 and clause 23, wherein theembolic material capture element conforms to an outer surface of thedilator assembly from the proximal end portion of the embolic materialcapture element to the distal end portion of the embolic materialcapture element when the embolic material capture element is in theinsertion configuration.

Clause 25. The method of any one of clause 22 through clause 24,wherein: the embolic material capture element has an outer surface thatextends between the proximal end portion of the embolic material captureelement and the distal end portion of the embolic material captureelement; and the outer surface of the embolic material capture elementis disposable distal to the outer sheath when the embolic materialcapture element is advanced through the blood vessel in the insertionconfiguration.

Clause 26. The method of any one of clause 22 through clause 25, whereinthe embolic material capture element comprises a shape-memory material.

Clause 27. The method of any one of clause 22 through clause 26,comprising retaining the embolic material capture element in theinsertion configuration at least partially via axial tension impartedinto the embolic material capture element via the dilator assembly.

Clause 28. The method of any one of clause 22 through clause 27, furthercomprising: advancing a distal portion of a treatment catheter throughthe inner sheath lumen to a position distal to the distal end portion ofthe embolic material capture element in the fully deployedconfiguration; and accomplishing a surgical task distal to the distalend of the embolic material capture element in the fully deployedconfiguration via the treatment catheter.

Clause 29. The method of clause 28, comprising: interfacing the embolicmaterial capture element in the fully deployed configuration with apatient's aorta; blocking flow of embolic material through the patient'saorta past the embolic material capture element; and deploying aprosthetic aortic valve from the distal end portion of the treatmentcatheter.

Clause 30. The method of any one of clause 22 through clause 29,wherein: the embolic material capture element comprises a filteringmembrane; and the method comprises filtering embolic material from bloodflowing through the blood vessel via the filtering membrane.

Clause 31. The method of any one of clause 22 through clause 30,comprising extracting embolic material through the inner sheath lumenwhile the embolic material capture element is in the fully deployedconfiguration.

Clause 32. An embolic material capture catheter having a restrainedinsertion configuration and a deployed configuration, the embolicmaterial capture catheter comprising: a filter sheath having an innerlumen and a filter sheath distal end portion; and a filter assemblyattached to the filter sheath distal end portion; the filter assemblycomprising an outer scaffold portion, an inner filter portion, and anintermediate portion; the outer scaffold portion having an outerscaffold proximal end portion and an outer scaffold distal end portion;the outer scaffold proximal end portion being attached to the filtersheath distal end portion; the outer scaffold portion being configuredto self-expand during reconfiguration of the embolic material capturecatheter from the restrained insertion configuration to the deployedconfiguration for engagement with a blood vessel inner surface; theinner filter portion having an inner filter proximal end portion and aninner filter distal end portion; the inner filter proximal end portionbeing attached to the filter sheath distal end portion; the inner filterportion being configured to capture embolic material from blood thatflows through the inner filter portion; the inner filter distal endportion being coupled with the outer scaffold distal end portion via theintermediate portion.

Clause 33. The embolic material capture catheter of clause 32, whereinthe inner filter portion is separated from the outer scaffold portion byan intervening annular space in the deployed configuration.

Clause 34. The embolic material capture catheter of clause 33, whereinthe intermediate portion is configured to capture embolic material fromblood flowing through the intermediate portion.

Clause 35. The embolic material capture catheter of clause 33, whereinthe intermediate portion is nonporous.

Clause 36. The embolic material capture catheter of any one of clause 33through clause 35, wherein the intermediate portion has a conical shapeconfigured to direct blood flow into the inner filter portion.

Clause 37. The embolic material capture catheter of any one of clause 33through clause 36, wherein the outer scaffold portion, the intermediateportion, and the inner filter portion are portions of an integrallyformed braided wire member.

Clause 38. The embolic material capture catheter of clause 37, furthercomprising a distal end sheet attached to the intermediate portion, thedistal end sheet being configured to block flow of embolic materialthrough the intermediate portion.

Clause 39. The embolic material capture catheter of clause 38, whereinthe distal end sheet is nonporous.

Clause 40. The embolic material capture catheter of clause 38, whereinthe distal end sheet has a porosity adapted to filter embolic materialout of blood flowing through the distal end sheet.

Clause 41. The embolic material capture catheter of any one of clause 33through clause 40, wherein the outer scaffold portion comprises distallyextending loops of wires configured for atraumatic engagement of theblood vessel inner surface.

Clause 42. An embolic material capture catheter having a restrainedinsertion configuration and a deployed configuration, the embolicmaterial capture catheter comprising: a filter sheath having an innerlumen and a filter sheath distal end portion; and a filter assemblyattached to the filter sheath distal end portion, the filter assemblycomprising an outer scaffold portion and an inner filter portion, theouter scaffold portion having an outer scaffold proximal end portion andan outer scaffold distal end portion, the outer scaffold proximal endportion being attached to the filter sheath distal end portion, theouter scaffold portion being configured to self-expand duringreconfiguration of the embolic material capture catheter from therestrained insertion configuration to the deployed configuration forengagement with a blood vessel inner surface, the inner filter portionhaving an inner filter proximal end portion; the inner filter portionbeing attached to outer scaffold portion, the inner filter portion beingconfigured to capture embolic material from blood that flows through theinner filter portion.

Clause 43. The embolic material capture catheter of clause 42, whereinthe inner filter portion is attached to the outer scaffold portion alongan entire length of the outer scaffold portion.

What is claimed is:
 1. A method of deploying an embolic material captureelement in a blood vessel, the method comprising: constraining aproximal end portion of an embolic material capture element viaattachment to a distal end portion of an inner sheath having an innersheath lumen; constraining a distal end portion of the embolic materialcapture element in an insertion configuration of the embolic materialcapture element via engagement of the distal end portion of the embolicmaterial capture element with a dilator assembly that extends throughthe inner sheath lumen, wherein the dilator assembly comprises a dilatorsheath and a deployment cap assembly, wherein the dilator sheath definesa dilator sheath lumen, and wherein the deployment cap assembly isslidably disposed in the dilator sheath lumen; advancing the embolicmaterial capture element in the insertion configuration through theblood vessel; and distally advancing the deployment cap assemblyrelative to the dilator sheath to release the distal end portion of theembolic material capture element from engagement with the dilatorassembly to reconfigure the embolic material capture element from theinsertion configuration to a fully deployed configuration viaself-expansion of the embolic material capture element.